Hitchcock went to great lengths to ensure that audiences were genuinely surprised by the infamous shower scene, which abruptly halts the Janet Leigh plotline and switches to the main act. He even went so far as to enforce a ‘no late entry’ policy. No one would have suspected that Hitchcock would kill off the top-billing actress only part way through. Although it happened because of scheduling conflicts, for the trailer he ended up filming a different actress – Vera Miles – being killed, which only confused people further. More of a good-natured deception that a true hoax – Hitchcock was pretty much doing the audience a favour.